1. Field of the Invention
The present invention relates to a process cartridge which is mounted in an image forming apparatus such as a laser printer or a copying machine, an end member which is arranged in the process cartridge, and a method of separating a process cartridge from an image forming apparatus body.
2. Description of the Related Art
An image forming apparatus represented by a laser printer, a copying machine, and the like includes a process cartridge which is attachable and detachable with respect to a body of the image forming apparatus (hereinafter, also referred to as “an apparatus body”).
The process cartridge is a member which forms contents to be shown such as letters and figures, and transfers the contents to a recording medium such as paper. The process cartridge includes a photosensitive drum in which the transferred contents are formed, and various types of means for operating on the photosensitive drum so as to form the contents to be transferred are collectively arranged in the process cartridge. As examples thereof, means for performing photographic developing, electrification, and cleaning can be exemplified.
The same process cartridge is attached to and detached from the apparatus body for maintenance or the old process cartridge is detached from the apparatus body so as to be replaced with a new process cartridge to be mounted in the apparatus body. A user of the image forming apparatus individually performs such attachment and detachment of the process cartridge. Therefore, from a viewpoint thereof, it is desirable that attachment and detachment of the process cartridge is easily performed.
Meanwhile, the photosensitive drum included in the process cartridge needs to rotate while being centered around an axial line during an operation. Therefore, during at least an operation, the photosensitive drum is configured to engage with a drive shaft of the apparatus body in a direct manner or through another member so as to rotate by receiving rotary power from the drive shaft. Accordingly, in order to perform attachment and detachment of the process cartridge with respect to the apparatus body, the drive shaft of the apparatus body and the photosensitive drum need to be disengaged (detached) from each other and remounted each time.
Here, if the photosensitive drum (the process cartridge) can move in an axial line direction of the drive shaft of the apparatus body so as to perform attachment and detachment, the aforementioned structure for attachment and detachment becomes relatively simple. However, from a viewpoint of miniaturizing the image forming apparatus, ensuring a space for attachment and detachment of the process cartridge, and the like, it is preferable that the process cartridge is drawn out in a direction different from the axial line direction of the drive shaft so as to be detached from the apparatus body and the process cartridge is thrust in the same direction so as to be mounted in the apparatus body.
Japanese Patent No. 2875203 as Patent Document 1 discloses that when a cover of the apparatus body is in a closed state, a drive force from the apparatus body side can be transmitted to the photosensitive drum, and when the cover is in an open state, a movement for detachment is performed so as to prevent the drive force from being transmitted to the photosensitive drum. Accordingly, the process cartridge can be attached to and detached from the apparatus body in the direction different from the axial line direction of the drive shaft.
In addition, there is a technology in which the photosensitive drum is provided with a gear, and the gear is caused to mesh with another gear which is driven by the apparatus body, thereby rotating the photosensitive drum.
JP-A-2008-233868 as Patent Document 2 discloses an invention in which the drive shaft of the apparatus body engages with a photosensitive drum unit through a rotary power transmission component having a trunnion structure attached to the photosensitive drum thereby rotating the photosensitive drum. Since the rotary power transmission component can vary the angle of the photosensitive drum with respect to the axial line on account of the trunnion structure, the drive shaft of the apparatus body and the photosensitive drum unit can easily engage with and be detached from each other.
WO 2012/113289 A1 as Patent Document 3 discloses a technology in which a claw member arranged in a bearing member engaging with the drive shaft is provided to be movable in a radial direction on account of an elastic member such as a spring. Accordingly, since the bearing member and the drive shaft reliably engage with each other, rotary power is appropriately transmitted, and since the claw member is movable during attachment and detachment, it is possible to achieve smoothly performed attachment and detachment.
Moreover, WO 2012/152203 A1 as Patent Document 4 discloses a technology in which the claw member attached to the shaft member engaging with the drive shaft is raised by pressing a projection at the center of the shaft member. Accordingly, since the bearing member and the drive shaft reliably engage with each other, rotary power is appropriately transmitted, and since the claw member is movable during attachment and detachment, it is possible to achieve smoothly performed attachment and detachment.
Japan Institute of Invention and Innovation, Journal of Technical Disclosure, No. 2010-502197 as Non-Patent Document 1 discloses a technology in which the bearing member engaging with the drive shaft is provided so as to be movable in the axial line direction on account of the elastic member such as the spring. Accordingly, during attachment and detachment between the bearing member and the drive shaft, the bearing member is urged by the elastic member so as to move and retract in the axial line direction, and thus, it is possible to achieve smoothly performed attachment and detachment.    Patent Document 1: Japanese Patent No. 2875203    Patent Document 2: JP-A-2008-233868    Patent Document 3: WO 2012/113289 A1    Patent Document 4: WO 2012/152203 A1    Non-Patent Document 1: Japan Institute of Invention and Innovation, Journal of Technical Disclosure, No. 2010-502197